Matrix with vector as element or 3d matrix or 3d tensor needed

Hi,

i am a new matlab user. I need to generate a above mentioned (subject) datatype. Is it possible. Thanks for your help in advance.

jfrenzel

 

[MikeyP]

Yes, you can define a 3D matrix. For example, a 3x3x3 matrix of 1's

A(:,:,1) = [1, 1, 1; 1, 1, 1; 1, 1, 1];
A(:,:,2) = [1, 1, 1; 1, 1, 1; 1, 1, 1];
A(:,:,3) = [1, 1, 1; 1, 1, 1; 1, 1, 1];
% A is a 3x3x3 3d matrix

The indices are in the form (row,column,page)

So to extract the second page of this 3d matrix, A, you would use

B = A(:,:,2); % B is a 3x3x1 3d matrix

However, this will still leave you with a 3D matrix (3x3x1) but the 3rd dimension will have a value of 1. Some matlab functions don;t like this. Using the "squeeze" function removes these "singleton" dimensions

C = squeeze(A(:,:,2); % C is a 3x3 2d matrix

I don't think you can perform tensor calculations directly though although there may be some toolboxes available.

Full versions of matlab support n-dimensional spaces. "Student" versions are restricted to 3d I think.

Older versions of Matlab do not support anything above 2D matrices.

M